As the federal and local investigation unfolds, evidence suggests that the Boston Marathon was allegedly planned and carried out by Tamerlan and Dzhokhar Tsarnaev. Some counterterror analysts have speculated that the Tsarnaev brothers may have planned a bigger operation than the marathon in the future. Were they inspired by al Qaeda-like, anti-American ideology that paints the United States as the root of all evil? It's too soon to tell what their motivation was, but it does appear that radical Islam influenced their alleged actions on April 15, 2013.

The Tsarnaev family immigrated to Boston from Kyrgyzstan over a decade ago. (Tamerlan was born in Kalmykia and Dzhorkhar was born in Dagestan.) Because they are of Chechen ethnicity they would have known all too well the more than 100,000 Chechens killed by the Red Army since the early 1990s, which turned Grozny, the Chechen capital, into rubble and led many of their countrymen to embrace the radical doctrines of Islamist groups who took on the leading role of resistance against Russia. To be sure, al Qaeda found fertile ground among the Chechens, converting many of them to the Salafist creed that preaches hatred against Russia, the United States, and other "infidel nations."

The bombs the brothers allegedly used were improvised explosive devices, IEDs, made from pressure cookers filled with explo¬sives, nails, and ball bearings. The IEDs could have been easily constructed by following instructions from online outlets such as from Inspire magazine, which details how one can "build a bomb in the kitchen of your mom."

Investigators believe these types of IEDs and the sheer amount of ammunition they possessed could indicate that they were inspired by al Qaeda. Consider the Jihadist guerrillas in Afghanistan, Pakistan, Iraq, and India who have used similar IEDs. The brothers also fit the prototype of these jihadists: young men who think they must defend who they consider to be oppressed people.

The older brother, Tamerlan, appeared to be influenced by radical Islam. His YouTube page includes two videos under the sub-category "terrorists." It also includes seven videos filed under "Islam." Both of the videos filed under "terrorists" cannot be viewed because they were removed.

Several of the videos under "Islam" are of Abdülhamid Al Juhani, an alleged Salafist scholar. The videos include Arabic audio and Russian text and pictures of Grozny. Another video under the "Islam" heading displays young men carrying assault rifles through a forest and the narrator says, "They demonize as terrorists anyone who supports Islam."

There are also several videos of Feiz Mohammed, an Australian sheik, who urges Muslims to kill enemies of Islam and praises martyrs. In a four hour DVD, Sheik Feiz talks about the Guantanamo Bay inmates, who he argues are "better than us. They are being examined through the best examination and the like of them worldwide." Feiz also references the mujaheddin who fought in Bosnia in the 1990s who spoke of jihad and were killed on the battlefield. "What a beautiful person to be associated with. Would you not like to be an associate of this person?"

Also, on Tamerlan's YouTube page were music videos featuring Timur Mutsuraev, a singer considered to be a hero among Chechens; one song is called, "We Dedicate Our Lives to the Jihad."

Over time, however, it became apparent that something was amiss.

The Wall Street Journal reported that Tamerlan became more confrontational in his religious beliefs in 2009 and even tried to convert the FBI agent to Islam who investigated him at the time. His uncle Ruslan Tsarni told The Today Show that he began to grow concerned about Tamerlan as early as 2009 when Tamerlan told him that he wanted to pursue "God's business" over work or school. And The Los Angeles Times and other news outlets reported that Tamerlan was thrown out of the Islamic Society of Boston mosque in Cambridge for outbursts he shouted in response to the Imam's message comparing Mohamed to Martin Luther King, Jr.

However, The LA Times refrained from mentioning that the ISB Cultural Center, a separate location from the mosque but still linked to it, "was founded as the overt arm of the Muslim Brotherhood in America," according to federal prosecutors in 2008. The ISB's teaching is primarily based on Islamists like Muslim Brotherhood spiritual leader Yousef al-Qaradawi and Sayyid Qutb, the Brotherhood cleric who influenced Osama Bin Laden. One of ISB's founders is Abdurrahman Alamoudi, who was convicted on terrorism-related charges in 2004 and is tied to al Qaeda and to being a secret Muslim Brotherhood operative.

Federal authorities are investigating a six-month trip Tamerlan allegedly took in 2012 to Chechnya and Dagestan. It is believed that upon his return an unknown religious leader in Cambridge, Mass., radicalized him.

Dzhokhar, who was active on Twitter, continues to be investigated. According to the SITE Intelligence group, which monitors Islamist websites, Dzhokhar followed a Twitter user named Al_firdausiA, which translated means, "the highest level of Paradise, Allah willing." Al firdausiA encouraged its followers to listen to audio of the American born al Qaeda terrorist Awlaki.

Today, Dzhokhar Tsarnaev was charged by federal prosecutors with using and conspiring to use a weapon of mass destruction against persons and property, a crime punishable by death.